Post on 15-Dec-2015
What can you say about the following global problems?
o Deforestationo Acid raino Toxic pollutiono Ozone holeo Global warming
Deforestation Tropical rainforests are being burnt and cut
because people need more land for agriculture. This is happening in Amazon basin in Brazil and SE Asia.
We also use more hard wood for making furniture.
Effects: Many plants and animals will become extinct. The forests absorb carbon dioxide in the process called photosynthesis. Without trees carbon dioxide levels will increase.
Solution: Alternative sources must be found for food and wood.
Acid rain Today rain contains harmful acid which can damage
the environment. pH shows on a scale of 0 to 14 how acid or alkaline the environment is. Coal burning in power stations releases sulphur dioxide into the atmosphere. This mixes with water in clouds and acid rain is formed. Car exhaust gases add other acids.
Effects: Acid rain in lakes kills fish and destroy leaves on trees and other plants.
Solutions: Remove the sulphur dioxide from chimneys of power stations and use alternative sources of energy.
Toxic pollution We produce lots of waste in the home. It must be
disposed of safely which is more expensive than to dump waste and toxic chemicals into rivers or holes in the ground. Chemicals are also used to kill pests in agriculture or to increase production and toxic waste from factories leaks into our waterways.
Effects: Toxic waste kills fish in lakes, rivers and the sea. Wastes or chemicals getting into our drinking water and food cause illness and diseases.
Solutions: Laws and regulations must be followed by all countries and must be updated as we get more knowledge.
Ozone hole The ozone layer, about 30km above the Earth´s
surface, absorbs dangerous ultra violet (UV) radiation.Over the Antarctic and other places such as Australia it is very thin. We release ozone damaging chemicals which destroy the ozone molecule and UV rays then reach the Earth´s surface.
Effects: UV causes damage to DNA of cells and various cancers can result especially after sunbathing.
Solutions: Ban the use of dangerous chemicals in aerosols, refrigerators and car air conditioning.
Global warming Carbon fossil fuels such as coal are burnt to produce energy
and produce large amounts of carbon dioxide that goes into the atmosphere. In a process called greenhouse effect high energy radiation from the solar system is trapped by gases such a carbon dioxide in the atmosphere. This heat energy keeps Earth temperature too high to support life.
Effects: More carbon dioxide means a larger greenhouse effect so the Earth´s overall temperature is increasing. This could cause rising sea levels, unpredictable weather in the form of flooding or drought, hurricanes and large loss of life.
Solutions: Change the way we produce energy and produce less carbon dioxide.
Complete the table with words from the list below, as shown in the category “foods”
Soap, low-powered cars, cotton and wool, inorganic fertilizers, high-powered cars, plastics, man-made-fibres, reuseable bottles, detergents
CATEGORY OLD NEWFoods natural foods artificial foodsMaterials metal, wood,leather
…………………..Food for plants natural manure …………………..Containers …………………. disposable plastic
containersCleaning …………………. ……………………Material for clothes …………………. ……………………Transport …………………. ……………………
Solution CATEGORY OLD NEWFoods natural foods artificial foodsMaterials metal, wood,leather plasticsFood for plants natural manure inorganic fertilizersContainers reuseable bottles disposable plastic
containersCleaning soap detergentMaterial for clothes cotton and wool man-made-
fibresTransport high-powered cars low-powered carsFINAL TASK:Now make sentences to express changes that have happened e.g.- A) Artificial foods have replaced natural foods - B) Natural foods have been replaced by artificial foods.